The invention relates to a cable with at least one transmission element, which is surrounded by a sheath of insulation material, as described in published German utility model DE 298 08 657 U1. The cables to which the invention refers are used, for instance, in industrial automation systems as flexible power supply cables, as combined cables with power and control wires, and as control lines. Another possible field of application is automobile technology. The “transmission element” can thus be a power core or a control or pilot core suitable for transmitting electrical or optical signals. Particularly important in these cables is the outer sheath, which must be able to withstand all possible mechanical, thermal and chemical stresses. Suitable materials are known, primarily thermoplastic elastomers (TPE), polyurethane (PU) or polyvinyl chloride (PVC). These cables should furthermore be easy to strip from their insulation for connecting purposes, e.g., to join connectors.
The known cable according to the aforementioned utility model DE 298 08 657 U1 meets these requirements. It comprises two side-by-side electrical cores provided with differently colored insulation and surrounded with a wrapping, which is called a separator. An internal polyvinyl chloride sheath produced by extrusion and having a dimensionally precise cylindrical outer surface is put over the separator. The internal sheath is surrounded by a braid of tinned copper wires. For mechanical protection an outer polyvinyl chloride sheath is provided. The sheath of the cable can be readily severed by means of a special tool with a knife, which in working position penetrates the sheath structure exactly up to the separator. Production of this cable is very costly, however.